Hard to find and only a few even available to purchase. This was a promotional item that Pyrex made for another company, Dainty Maids, and it was sold through catalog sales. Manufactured in the 1950s, the bowl does not feature a Pyrex stamp or any kind of marking, and the name “turquoise diamonds” is non-standard. This piece is in Excellent Glossy Condition. Pattern is bright and bold. Key Identification Details Pattern Name: Commonly referred to as "Turquoise Blue Diamonds" or "Dainty Maid Diamonds". Manufacturer: While widely attributed to Pyrex, these bowls were originally produced as a promotional item for the brand Dainty Maid. Markings: Most authentic versions of this specific bowl are unmarked, meaning they do not feature the standard Pyrex backstamp on the bottom. History One of the rarest Pyrex patterns, Turquoise Diamonds, remained a mystery until 2018 when the first Turquoise Diamonds bowl was discovered by a collector in its original box. Later, it was discovered that the bowl had been manufactured for a brand known as Dainty Maid – this was the reason why the bowl did not feature Pyrex markings.